This large prospective study attempts to add to available knowledge of the perinatal factors associated with motor handicaps in childhood, the primary goal is being to identify areas for possible preventive efforts. Studies on the prevalence, on perinatal factors and neonatal signs in the early recognition of cerebral palsy have been published. Data on demographic analysis and a univariate screen of maternal and pediatric factors associated with cerebral palsy are available. Studies on early recognition of cerebral palsy, and on natural history of children with early motor abnormalities, have been published. A study on obstetric factors as antecedents of cerebral palsy has been submitted for publication. An investigation of the antecedents of a major risk factor for cerebral palsy, very low birthweight, is in preparation. Analysis of forward risks for cerebral palsy based upon maternal and obstetric factors is being programmed, and multivariate analysis is nearing completion.